Find out how many external displays your Mac supports

Why it happens

Each Mac chip can drive a fixed number of screens, and no setting changes it. The plain M1 and M2 chips in MacBook Air and the 13-inch MacBook Pro drive one external display, and so does the plain M3 in the 14-inch MacBook Pro. Many other Macs, including those with Pro or Max chips, drive two or more, so your model's Tech Specs page is the one to trust.

How to fix it

1. Choose Apple menu > About This Mac. Note the Chip line, such as Apple M2 or Apple M3 Pro, and the model name and year at the top.

   Apple menu›About This Mac

2. Search for your model's Tech Specs on Apple's support website, and look under Display Support. It lists how many external displays it supports and at what resolution.

3. As a rough guide for laptops: MacBook Air and 13-inch MacBook Pro with M1 or M2, and the 14-inch MacBook Pro with the plain M3 chip, support one external display. A MacBook Air with M3 supports two, but only with its lid closed. Pro chips usually support two, and Max chips up to four.

4. Connect your displays to the ports the Tech Specs page names. Some Macs drive a display only from certain ports, such as HDMI or Thunderbolt.

Still not fixed?

1. Second screen stays black on a Mac that supports one? That's the chip's limit, not a fault. Mirroring won't add a screen, and a second display needs a Mac whose Tech Specs list two or more.

2. On a MacBook Air with M3, close the lid with power, a keyboard and a mouse connected. The second display should then come on.

3. A plain hub or adapter doesn't raise the limit. Some docks add extra screens using their own driver software, which can be fine for documents but may stutter with video.

4. If a supported display isn't showing, open Displays, hold Option and click Detect Displays, then try another cable and restart.

   Displays

5. If your Mac supports the number you've connected and one still won't show with a known-good cable, contact Apple Support or a repair shop. A port can fail, and that's a hardware repair.